A transistor can regulate current or voltage flow and acts as a switch or gate for electrical signals. Transistors include a semiconductor material capable of carrying a current. A small change in the input current or voltage can produce a large change in the current passing through the transistor. The transistor can thus act as a switch, opening and closing an electronic gate many times per second. Transistors are basic elements in integrated circuits (ICs), which can use very large numbers of transistors interconnected with circuitry and baked into a single silicon microchip. Today's computers use circuitry dominated by complementary metal oxide semiconductor (CMOS) technology.